Study Question: What amount of additional solar is required to make utility bills of an all-electric apartment building cheaper than its gas hybrid counterpart, built to the 2019 California Title 24 New Construction Low Rise Residential Multifamily Energy Code in all Southern California Edison Territory Climate Zones?
Summary of Study: Three scenarios were studied using a two-story multifamily project, all designed to meet California’s 2019 Title 24 Code with minimum code compliant PV arrays. The scenarios studied are as follows:
Minimum prescriptive compliance options for all-electric and gas-hybrid construction
High performance mechanical system options for all-electric and gas-hybrid construction
Adding more PV to the all-electric Minimum Prescriptive and High-Performance options until the utility bills are lower than the gas-hybrid options
The two-story multifamily project of study consists of 26 residential apartments (Figure 1) and was modeled using Energy Pro v8.0.3. The building of study was modeled in Southern California Edison (SCE) Territories 5, 9, 10, 13, 14 and 16 residing in California Energy Commission (CEC) Climate Zones 6, 9, 10, 13, 14 and 16 respectively.
Figure 1: The apartment building of study, modeled in all Southern California Edison Territories